Field of the Invention
The present invention relates to a diode device and a method for manufacturing the same, and in particular, it relates to a Schottky diode having the properties of low leakage current and high breakdown voltage.
Description of the Related Art
A Schottky diode composed of gallium nitride (GaN) has properties such as high breakdown voltage, high electric current and suitable for performing at high temperature, and therefore is compatible for the application in high-power electronic circuits. Furthermore, the polarization effect, a characteristic property of gallium nitride, results in the AlGaN/GaN heterostructure having a high-concentration of two-dimensional electron gas (2DEG), and therefore, it is possible to provide transmission under low series resistance and high current.
However, the Schottky diode formed by such a heterostructure has a problem wherein the turn-on voltage is too large due to the Schottky metals formed on aluminum gallium nitride (AlGaN) having a wide bandgap. In order to solve the problem, the traditional manufacturing methods for Schottky diodes developed for decreasing the turn-on voltage are formed by more complex processes with higher processing cost and the tendency for there to be a greater leakage current in the Schottky diodes, negatively affecting to the performance of the Schottky diodes.
As a result, it is necessary to develop a brand new diode device and a method for manufacturing the same to solve or improve the described problems, and therefore to provide a Schottky diode having the properties of low leakage current and high breakdown voltage.